1. Field of the Invention
The present invention relates to an automatic transmission apparatus, for example mounted on a vehicle, which has a shift lever for changing a range positions of a range changing mechanism, such as P (Parking), R (Reverse), N (Neutral), D (Drive), 2 (Second) and L (Low), and reduces a passenger's strain for changing the positions of the range changing mechanism by applying an assist force to an operating force of the passenger.
2. Description of the Related Art
FIGS. 1 to 3 shows a structure of a conventional automatic transmission apparatus for a vehicle (for example, refer to a Japanese patent application laid open publication: H11-286225).
As shown in FIGS. 1 to 3, a conventional automatic transmission apparatus 1 for a vehicle is comprised of a shift lever 3 provided in a steering column 2 of a vehicle, a servo actuator 5 applying an assist force to a manual shift operating force for changing a gear position of a changing transmission 4, Bowden cables 6a and 6b connecting the shift lever 3 and the servo actuator 5, a range changing shaft 7 transmitting a rotating operation of the shift lever 3 via the Bowden cables 6a and 6b, a fan-shaped gear 8 connected to the range changing shaft 7 and engaged with a pinion 5A rotated by the servo actuator 5, and a shift lever sensor 9 detecting a position of the shift lever 3. Further, the range changing shaft 7 is rotated corresponding to an amount of operation of the shift lever 3.
However, since the conventional automatic transmission apparatus 1 for the vehicle is provided independently with the shift lever 3, the servo actuator 5 and the shift lever sensor 9, and therefore a transmitting means such as the Bowden cables 6a and 6b connecting the shift lever 3 and the servo actuator 5 are indispensability needed. Accordingly, there are problems that the number of the parts constituting the conventional transmission is increased, and the conventional an entire apparatus is large-scaled and is heavy.
Accordingly, the present invention is made to address the problems mentioned above, and an object of the present invention is to provide an automatic transmission apparatus for a vehicle in which a number of parts can be reduced, and an entire apparatus can be downsized and save weight.